Environmental Engineering Reference
In-Depth Information
BACKGROUND / LITERATURE
REVIEW
through fluctuations in price, supply and demand
(BBC Weather Centre, n.d.).
Energy is extracted through the process of burn-
ing fossil fuel (combustion) and then converted to
other forms of the energy such as heat and electric-
ity. Carbon (C) and Hydrogen (H) react during
the combustion process to form Carbon Dioxide
(CO
2
). Heat is released during this process. The
release of CO
2
and heat into the atmosphere is a
major contributor to the Greenhouse effect and
global climate change, both of which are now an
increasing concern throughout the world.
Environmental Issues
Many researchers have found that non-renewable
energy resources, such as oil and natural gas, are
nearing depletion due to increasing human use.
The most valuable non-renewable source of energy
is fossil fuels. Its price affects the entire global
economy due to production instability and lack of
consistant oil pricing. By comparison, renewable
energy resources are able to support human energy
needs without depletion. Although renewable en-
ergy resources are currently unable to completely
displace all of our non-renewable energy use, many
scientists are making advancements in renewable
energy technology. It can be hoped that in time,
science will enable the complete substitution of
non-renewable energy resources for fossil fuels
(McKinney and Schoch, 2003).
Fossil fuels are created by the decomposition
of living organisms. These can be separated into
three types: coal, natural gas and oil. Coal is a
solid fossil fuel created by the decomposition of
land vegetation. When compared with other fossil
fuels, coal is quite abundant and easily recovered
in many locations. Many developing countries
depend on coal for energy because they cannot
afford other fossil fuels. India and China are the
main consumers of coal.
Natural gas is a vaporous fossil fuel that is
abundant, useful and relatively clean compared
to other fossil fuels. It is formed from the re-
mains of marine microorganisms. Natural gas is
used in many developed countries. Oil, a liquid
fossil fuel, is the most widely used and valuable
fossil fuel. It is also created from the remains
of marine microorganisms deposited on the sea
floor. Crude oil is refined and used for fuel in
cars and other forms of transportation. Oil is not
available everywhere on earth, but is found only
in specific areas. Consequently, it is a powerful
What is the Greenhouse Effect?
The sun heats the earth by radiating solar rays.
Some of these rays are absorbed by greenhouse
gases, such as CO
2
, that are created by burning
fossil fuel
.
These greenhouse gases cause the
earth's temperature to rise, causing global climate
change. Effects include increases in the average
air and ocean temperatures, widespread melting
of polar icecaps, and a rising sea level. The heat-
ing effect caused by the production of too many
greenhouse gases, is known as “Global Warming.”
(BBC Weather Centre, n.d.) (Intergovernmental
Panel of Climate Change, n.d.).
Consequently, the burning of fossil fuels is
one of the most critical problems the world is
currently facing. In the United States, more than
90% of greenhouse gas emissions come from the
burning of fossil fuels. This is one of the major
reasons for supporting the use of renewable alter-
native energy sources, such as cellulosic ethanol.
Research shows that ethanol burns cleaner and
produces less carbon dioxide (CO
2
) then gasoline.
M. LaMonica in the NRDC study states that “mak-
ing ethanol from the cellulose in agricultural and
forestry waste produces less greenhouse gases than
consuming gasoline from refining.” (Wikipedia,
2008a). According to this study, ethanol can reduce
the greenhouse gas emissions between twenty and
eighty percent depending on the feedstock used
to produce it.
